<template>
  <div id="app">
    <div>
      <span>姓名:</span>
      <input type="text" v-model.trim="userName"/>
    </div>
    <div>
      <span>年龄:</span>
      <input type="number" v-model.number="userAge"/>
    </div>
    <div>
      <span>性别:</span>
      <select v-model="gender">
        <option value="男">男</option>
        <option value="女">女</option>
      </select>
    </div>
    <div>
      <button @click="addOrEditFn">添加/修改</button>
    </div>
    <div>
      <table
        border="1"
        cellpadding="10"
        cellspacing="0"
        v-show="arr.length > 0"
      >
        <tr>
          <th>序号</th>
          <th>姓名</th>
          <th>年龄</th>
          <th>性别</th>
          <th>操作</th>
        </tr>
        <tr v-for="(obj,index) in arr" :key="index">
          <td>{{index + 1}}</td>
          <td>{{obj.name}}</td>
          <td>{{obj.age}}</td>
          <td>{{obj.sex}}</td>
          <td>
            <button @click="del(indx)">删除</button>
            <button @click="edit(index)">编辑</button>
          </td>
        </tr>
      </table>
    </div>
  </div>
</template>
<script>
export default {
  data () {
    return {
      userName:'',
      userAge:0,
      gender:"",
      editIndex:null,
      arr:[
        {
          name:'小蓝',
          age:19,
          sex:"女"
        },
        {
          name:'小丽',
          age:18,
          sex:"男"
        },
        {
          name:'小美',
          age:20,
          sex:"女"
        }
      ]
    }
  },
  methods: {
    addOrEditFn(){
      let newObj ={
      name:this.userName,
      age:this.userAge,
      sex:this.gender
    }
    if (this.editIndex !== null) {
      this.$set(this.arr,this.editIndex,newObj)
      this.editIndex = null
    }else{
      this.arr.push(newObj)
    }
    
    },
    del(index){
      this.arr.splice(index,1)
    },
    edit(index){
      let editObj = this.arr[index];
      this.userName = editObj.name;
      this.userAge = editObj.age;
      this.gender = editObj.sex;
      this.editIndex = index
      // 把正在编辑的索引值保存起来
    }
  }
}
</script>
